Core A Imaging and Dosimetry, will provide 4 support ares to the Program Project. These include (1) the provision of animal and clinical imaging, (2) modeling of antibody pharmacokinetics using ADAPT II and SAAM software, (3) estimation of absorbed radiation doses, and (4) counting quality assurance in radioassays. Images provide a guide to disease extent, spread and surgical treatment. In addition, they are the primary input into the estimation of organ and tumor uptake in the patient. Modeling is needed since we require biodistributions of in-111 Mabs to stand in for the subsequent Y-90 Mab; thus, we use the image data as the modeler's input to predict the therapy application's biodistribution in patients. We will compare model predictions of organ and tumor uptake with surgical samples. Radiation dose is estimated using the model's individual organ uptake time-activity integrals. Such dose estimates will be compared with clinical data such as blood cell levels. Finally, counting experiment quality assurance will be determined from Core A. The Imaging and Dosimetry core will continue to provide support to Dr. Wong, Dr. Wu and Dr. Shively. In addition, we will maintain our close association with Dr. Raubitschek 1) as well as Dr. Maryon. Additionally, this Core will provide imaging and dose estimation service for the animal studies. External collaborations will continue with AAPM Task Group 7 and the RIDIC center at Oak Ridge TN (Mike Stabin).